Tetragnatha bifurcata Li & Liu, 2022

Li, Song-lin, Liu, Ping & Peng, Xian-jin, 2022, Three new species of the genus Tetragnatha Latreille, 1804 (Araneae, Tetragnathidae) from China, ZooKeys 1125, pp. 87-101 : 87

publication ID	https://dx.doi.org/10.3897/zookeys.1125.86905
publication LSID	lsid:zoobank.org:pub:8B173267-C53A-4018-BFF2-E8397DD6EA1F
persistent identifier	https://treatment.plazi.org/id/27CEAEB3-4814-4DFD-AAB4-745CE7C240A1
taxon LSID	lsid:zoobank.org:act:27CEAEB3-4814-4DFD-AAB4-745CE7C240A1
treatment provided by	ZooKeys by Pensoft
scientific name	Tetragnatha bifurcata Li & Liu
status	sp. nov.

Treatment

Tetragnatha bifurcata Li & Liu sp. nov.

Figs 1 View Figure 1 , 2 View Figure 2 , 7 View Figure 7

Type material.

Holotype ♂: China, Yunnan Province: Tengchong County, Houqiao Township, Zhaobitang Village, 25.5378°N, 98.2094°E, 2480 m, 29.V.2006, X.P. Wang & P. Hu leg. (Wang060529-1). Paratypes: 2♂♂ 3♀♀, same data as holotype (Wang060529-1); 5♂♂, Tengchong County, Houqiao Township, Zhaobitang Village, 25.3986°N, 98.3053°E, 2374 m, 27.V.2006, X.P. Wang & P. Hu leg. (Wang060527-2); 1♂ 1♀, Lushui County, Luzhang Township, Yaojiaping River 25.9772°N, 98.7109°E, 2527 m, 19.V.2005, D. Kavanaugh et al. leg. (2005-015A).

Etymology.

The specific epithet is derived from the Latin adjective bifurcus, referring to the bifurcate distal end of the conductor.

Diagnosis.

The new species resembles T. tortilis sp. nov. (Figs 5 View Figure 5 , 6 View Figure 6 ). Males of the two species are similar in having a tapered dorsal spur on the chelicera, and the conductor with 2 folds, but can be distinguished by: (1) the distal portion of conductor bifurcated in T. bifurcata sp. nov. (Fig. 1L View Figure 1 ) (vs. not bifurcated; Fig. 5K View Figure 5 ); (2) the paracymbium with a pointed tip and terminal part located beyond the tegulum in ventral view (Fig. 1I View Figure 1 ) (vs. with blunt tip and terminal part located at the middle part of the tegulum; Fig. 5I View Figure 5 ). Females of the two species are similar in the shape of the epigynal fold and the absence of a central membranous sac in the vulva, but can be distinguished by: (1) the distance between the guide tooth and the second tooth of the upper row of chelicera slightly longer than the distance between the second tooth and the third tooth of the upper row of chelicera in T. bifurcata sp. nov. (Fig. 2E View Figure 2 ) (vs. the distance between the guide and the second tooth of the upper row of chelicera 3 × longer than the distance between the second tooth and the third tooth of the upper row of chelicera; Fig. 6E View Figure 6 ); (2) the spherical anterior spermathecae are ~ 1.5 × larger than the posterior spermathecae (Fig. 2H View Figure 2 ) (vs. anterior spermathecae oval and ~ 5 × larger than the posterior spermathecae; Fig. 6H View Figure 6 ).

Description.

Male (holotype) (Fig. 1A-F View Figure 1 ). Total length 3.60. Carapace 1.31 long, 0.92 wide, yellowish brown, fovea and cervical and radial grooves distinct. Eye sizes and interdistances: AME 0.06, ALE 0.12, PME 0.12, PLE 0.10; AME-AME 0.08, AME-ALE 0.12, PME-PME 0.12, PME-PLE 0.10. MO anterior width 0.17, posterior width 0.24, length 0.22. Clypeus 0.08 high. Labium dark brown, with thickened edge. Sternum brown with dark edge. Legs yellowish brown, with sparse spines. Leg measurements: I, 11.45 (3.12, 3.84, 3.23, 1.26); II, 8.15 (2.38, 2.72, 2.19, 0.86); III, 3.73 (1.32, 1.04, 0.91, 0.46); IV, 7.16 (2.42, 2.21, 1.86, 0.67). Chelicera: ~ 1/2 carapace length; dorsal spur tapered, with blunt tip; AXu absent; upper row with 5 teeth: Gu slightly smaller than U2, U2 almost equal to U3 in size, distance between U2 and Gu longer than distance between U2 and U3, other teeth decreasing in size gradually; AXl absent; lower row with 5 teeth: Gl slightly smaller than L2, L2 largest, other teeth decreasing in size gradually. Abdomen 2.26 long, 0.72 wide, dorsum yellowish brown, with 5 pairs of dark spots laterally and brown longitudinal line medially, both lateral sides with longitudinal dark band throughout entire abdomen; venter yellowish brown, median band brown.

Palp (Fig. 1G-L View Figure 1 ). Paracymbium with pointed tip, notch shallow, translucent lobe elongated, ~ 1/3 width of paracymbium, knob thumb-shaped. Tegulum oval, ~ 2 × as wide as long. Conductor with 2 folds, distal portion bifurcated, upper branch thicker with slightly swollen tip, lower branch thinner with blunt tip. Embolus partly enveloped by conductor.

Female (Wang060529-1) (Fig. 2A-F View Figure 2 ). Total length 4.02. Carapace 1.38 long, 0.91 wide. Eye sizes and interdistances: AME 0.06, ALE 0.06, PME 0.07, PLE 0.07; AME-AME 0.05, AME-ALE 0.10, PME-PME 0.09, PME-PLE 0.09. MO anterior width 0.17, posterior width 0.24, length 0.20. Clypeus 0.04 high. Leg measurements: I, 10.31 (2.85, 3.50, 2.92, 1.04); II, 7.13 (2.13, 2.30, 1.92, 0.78); III, 3.24 (1.09, 0.94, 0.80, 0.41); IV, 6.39 (2.20, 1.98, 1.63, 0.58). Chelicera: AXu absent; upper row with 5 teeth: Gu slightly smaller than U2, U2 largest, other teeth almost equidistant and decreasing in size gradually; AXl absent; lower row with 6 teeth: Gl slightly smaller than L2, L2 largest, other teeth decreasing in size gradually. Abdomen 2.71 long, 0.85 wide, dorsum without dark spots but with dispersed pale spots; venter with pale spots on both sides. Color paler than that in male.

Epigyne (Fig. 2G, H View Figure 2 ). Fold ~ 3 × wider than long. Vulva composed of 2 pairs of spherical spermathecae, diameter of anterior pair ~ 1.5 × of posterior pair, anterior pair spaced by 1 diameter of anterior spermatheca, posterior pair spaced by 3 diameters of posterior spermatheca. Central membranous sac absent.

Distribution.

Known only from the type locality (Fig. 7 View Figure 7 ).